Olefin oxidation catalyst

ABSTRACT

THE PRESENT INVENTION RRELATES TO A NOVEL CATALYST CORRESPONDING TO THE EMPIRICAL FORMULA   NIA COB FEC BID MEE HH MOF OG   WHEREIN ME REPRESENTS AT LEAST ONE ELEMENT SELECTED FROM THE GROUP OF TIN, MAGNESIUM, CHROMIUM, ZINC, MANGANESE TITANIUM AND TUNGSTEM, H REPRESENTS AT LEAST ONE ELEMENT SELECTED FROM THE GROUP OF POTASSIUM, RUBIDIUM AND CESIUM, AND A, B, C, D, E, F, G AND H ARE NUMBERS OF ATOMS OF NI, CO, FE, BI, ME, MO, O AND H RESPECTIVELY, IF MORE THAN TWO ELEMENTS ARE PREFERRED IN THE CASE OF ME AND H, E AND H MEANS THE TOTAL NUMBERS OF THOSE ELEMENTS, WITH THE PROVISO THAT WHEN F IS 12, A IS 0 TO 6, B IS 0 TO 20, C IS 0.5 TO 8, D IS 0.1 TO 7, E IS LESS THAN 3.0 EXCLUDING ZERO, H IS MORE THAN 0 AND NO MORE THAN 0.5, AND G IS A NUMBER WHICH IS DETERMINED BY THE VALANCE REGUIREMENTS OF NI, CO, FE, BI, ME, H, AND MO. G IS ABOUT 36 TO 90. THE CATALYST OF THE INVENTION IS USEFUL IN OXIDATION OF OLEFINS, AND IN PARTICULAR IN THE PRODUCTION OF METHACROLEIN OR 1,3-BUTADIENE AND METHACROLEIN SIMULTANEOUSLY BY THE OXIDATION OF OLEFIN CONSISTING OF ISOBUTYLENE OR BUTENE MIXTURE CONTAINING ISOBUTYLENE AND N-BUTYLENE WITH MOLECULAR OXYGEN OR AIR. ACCORDING TO THE PRESENT INVENTION, THE CATALYST EMPLOYED IN A VAPOR PHASE OXIDATION INCREASE THE YIELD OF METHACROLEIN WITHOUT EXCESSIVE OXIDATION OF OLEFINS TO UNDESIRED HIGHER OXIDATION PRODUCTS OF CARBON SUCH AS CARBON MONOXIDE AND CARBON DIOXIDE.

United States Patent 015cc 3,825,502 Patented July 23, 1974 U.S. Cl. 252-456 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to a novel catalyst corresponding to the empirical formula:

Ni,,Co l e Bi Me H Mo o wherein Me represents at least one element selected from the group of tin, magnesium, chromium, zinc, manganese titanium and tungsten, H represents at least one element selected from the group of potassium, rubidium and cesium, and a, b, c, d, e, f, g and h are numbers of atoms of Ni, Co, Fe, Bi, Me, Mo, 0 and H respectively, if more than two elements are preferred in the case of Me and H, e and h mean the total numbers of those elements, with the proviso that when f is 12, a is 0 to 6, b is 0 to 20, c is 0.5 to 8, d is 0.1 to 7, e is less than 3.0 excluding zero, h is more than 0 and no more than 0.5, and g is a number which is determined by the valence requirements of Ni, Co, Fe, Bi, Me, H, and Mo. g is about 36 to 90. The catalyst of the invention is useful in oxidation of olefins, and in particular in the production of methacrolein or 1,3-butadiene and methacrolein simultaneously by the oxidation of olefin consisting of isobutylene or butene mixture containing isobutylene and n-butenes with molecular oxygen or air.

According to the present invention, the catalysts employed in a vapor phase oxidation increase the yield of methacrolein without excessive oxidation of olefins to undesired higher oxidation products of carbon such as carbon monoxide and carbon dioxide.

BACKGROUND OF THE INVENTION Mnay of the catalysts for preparing methacrolein by oxidizing isobutylene have been previously disclosed. The catalysts which were composed of (1) tellurium oxidemolybdenum Oxide system, resulted in a relatively good yield of methacrolein [in British Pat. No. 1,014,121 (1965, I.C.I), French Pat. No. 1,380,884 (1.01) and Japanese Patent Publications Nos. 3,562/1969 (Montecatini), 8,992/ 1969 (Mitsubishi Rayon) and 25,046/ 1969 (Toa Gosei)]. Another group (2) of catalysts containing iron, bismuth, phosphorus, molybdenum have been also disclosed for this process in US. Pat. No. 3,171,859, Japanese Patent Publications Nos. 2,324/ 1968 (Nippon Kayaku) and 22,526/ 1970 (Asahi Kasei). While the yields of methacrolein with the group (1) of catalyst containing tellurium are good in general, the life of those of group (1) is very short. It is also disadvantageous for industrial viewpoint that these catalysts contain the amount of -20% of expensive tellurium oxide.

The group (2) of catalysts containing bismuth-phosphorus-molybdenum and iron have a high activities as compared with another one, nevertheless, have an inferior selectivity for methacrolein.

According to the process of Japanese Patent Publications Nos. 2,324/ 1968, 16,602/1967 and 2,413/ 1967, with Bi-Mo system catalyst 95-98% of isobutylene fed to the reactor is consumed in a single pass over the catalyst and only 35-45% of the isobutylene consumed is converted to methacrolein and most of the remainder is converted to carbon diand monoxide. The highest single pass yield of methacrolein based on the total isobutylene fed in Japanese Patent Publication No. 2,413/1967 is only 41%.

In the process of US. Pat. No. 3,171,859, about 50% of single pass yield is obtained, but its value is not satisfactory for commercial yield, comparing that high single pass yield of acrolein are obtained in the oxidation of propylene.

On the other hand, a process for the simultaneous preparation of methacrolein and 1,3-butadiene have been also disclosed in Japanese Patent Publication No. 7,881/1967. In this publication, the process carried out over a catalyst comprised of oxides of V, Bi and Mo, and the highest yield of 67% for methacrolein, but that of only 76% for 1,3-butadiene are obtained.

SUMMARY According to the process of the present invention, the highest single pass yield of 1,3-butadiene from n-butenes under the proper operating conditions amounts to about 87% and that of methacrolein from isobutylene amounts to about 77%.

:Prior to the oxidation of the single component of either n-butenes or iso butylene, a purified single component of butene should be prepared by means of a physical or chemical separation of isobutylene from n-butenes. At present, industrial sources for butenes are provided from 0., fractions formed in petroleum naphtha cracking and residue obtained by extracting out 1,3-butadiene from the 0., fractions. This residue, however, still contains four butenes (i.e. isomers of butene-l, cis-2-butene, trans-2- butene and isobutylene) which are quite similar to each other in both physical and chemical properties and, therefore, separation and purification of a desired component are not easy and thus single component of butenes is too expensive to be used as industrial starting material.

The products obtained by the process of the present invention are mainly composed of 1,3-butadiene and methacrolein with a boiling point of 40 C. and 68 C., respectively and, therefore, the separation of these prod ucts can be done easily by a simple physical operation.

When the mixture of different butenes is used as starting materials, the four butenes are generally different from each other in reactivity, the order being, isobutylene butene-1 cis-2-butene trans-2-butene. In the presence of the catalyst according to the present invention, the optimum reaction temperatures of at least the main components, n-butenes, particularly, butene-1 and isobutylene is nearly the same. This is a great advantage that nearly the same temperature can be preferred in the simultaneous reaction to obtain same conversions. It means that no limitation is made in mixing ratio of starting olefins and that the mixture of said two butenes in any proportion can be used. It is also advantageous in a reaction wherein starting materials are circulated, and this is quite significant from industrial viewpoint.

It is another advantage that the addition of the elements Me decreases in the temperature of oxidations. In the present catalyst, 2-80390 C. of the salt bath temperature is preferred, which is lower by 30-50 C. than in the prior one.

DETAILED DESCRIPTION The use of the catalyst of this invention will be now considered in more detail.

The process of this invention will be now considered in more detail in regard to the specific desired products,

Selectivity to methacrolein percent Mols of methacrolein obtained Mols of isobutylene converted Singe Pass Yield of 1,3 butadiene or methacrolein percent Mols of 1,3-butadiene or methacrolein Mols of n-butenes or isobutylenefed ConversionX Selectivity The useful catalyst in the process of the present invention is composed from mixture compound or complex made up of the oxides of nickel and/or cobalt, iron, bismuth, molybdenum, elements represented by Me and H. The composition is conveniently expressed in the empirical formula mentioned above.

Of the above compositions, suitable preferred catalysts are given, when f is 12, a is -5, b is 1-15, 0 is 1-6, d is 1-5, e is less than 3.0 excluding zero, g is 4080 and h is more than 0 and no more than 0.5. And moreover, more suitable ones are obtained, when f is 12, a is 0-5, b is 2-12, 0 is 1-5, d is 1-5, e is less than 3.0 excluding zero, g is 40-70 and h is more than 0 and no more than 0.2.

Among the elements Me mentioned above, suitable elements are magnesium and chromium.

The catalyst of this invention is usually prepared by adding aqueous solution of the suitable water-soluble salt of nickel, cobalt, iron and bismuth, the group of H and Me compounds to aqueous solution of suitable molybdate such as ammonium molybdate. The resulting slurry is then heated with a carrier. The solid cake which is formed by removing water is then calcined at an elevated temperature in the air or oxygen stream. Molybdenum oxide, or molybdic acid may be suitably used in place of ammonium molybdate. Suitable water-soluble salts for the preparation of the catalysts of this invention are nickel nitrate, cobalt nitrate, ferric nitrate, potassium nitrate and bismuth nitrate. -For the group of Me, tin chloride, zinc nitrate, magnesium nitrate, ammonium chromate, ammonium para-tungstate etc. are preferably used. The catalyst embodied herein is particularly effective when deposited upon a carrier. Suitable carriers include, silica, silicon carbide and alumina, and the silica gel or sol is particularly effective.

Catalysts are used in many solid physical forms such as grain and pellets. The catalyst of this invention is suitable for use in a fixed, fluidized, or moving bed reactor. The catalytic oxidation process of this invention is carried out at a temperature of from 250 to 500 C., preferably 280 to 390 C., and under a pressure of from 015 to atmospheres absolute. In the oxidation of isobutylene and/or n-butenes, the contact time of feed gaseous mixture of air and isobutylene and/or n-butenes with the catalyst is usually preferred from 0.1 to 12 seconds and preferably from 0.5 to 8 at real temperature and pressure.

The feed for the processes usually requires the presence of from 0.5 to 4.0 mols, preferably 1.6 to 3.0 mols, of oxygen in the form of air per mol of olefin consisting of isobutylene or butene mixture containing n-butenes and isobutylene. Water in the form of steam is fed to the reactor along with the gaseous mixture of said olefin and air. The mole ratio of water per mol of olefin may be in the range of 1 to 20, and a ratio of 2 to 6 is pre- 4 ferred. A large volume of water in the feed effects a dilution and removal of the reaction heat, but little of water need be employed if the heat can be efiiciently removed as in a molten potassium nitrate salt, or in a fluidized solid bath. When olefin is used as butene mixture in the present invention, the more the ratio of nbutenes is high, the more the single pass yield of methacrolein is high.

The process of the present invention is further illustrated by the following example.

EXAMPLE 1 87 grams of cobalt nitrate and 45 grams of ferric nitrate were dissolved in ml. of distilled water respectively. 0.25 grams of potassium nitrate, 9.6 grams of magnesium nitrate and 18 grams of bismuth nitrate with a small amount of conc. nitric acid were dissolved in about 30 ml. of water. All of foregoing solution were added to the aqueous solution of 80 grams of ammonium molybdate. In the slurry, about 23 grams of silica gel (fine powder) were suspended. The resulting slurry was dried and then heated to 250 C. The resulting mass was pulverized, formed to a suitable size and calcined at 700 C. for 6 hours in the air.

The composition of the catalyst was represented by the following formula:

120 ml. of the catalyst obtained above were filled in a reactor with 21 mm. in diameter dipped in a salt bath which was maintained at 330 to 340 C. Olefin used as a starting material was composed of 0.5 mol fraction of butene-1 (98.0% of purity, and additional 2% of butene-2) and 0.5 mol fraction of isobutylene (97.2% of purity and additional 2.5% of butanes). The gaseous mixture of this olefin, air and steam in the molar ratio of 1:2.2:6.5 was passed over the catalyst at the contact time of 5 seconds.

The result was given as follows:

Percent Conversion of isobutylene 96.5 Single Pass Yield of methacrolein 77.2 Single Pass Yield of methacrylic acid 2.9

Conversions of isobutylene to undesired higher oxidation products of CO and CO were only 2.1 and 4.5%, respectively. 1,3-butadiene was simultaneously produced with a yield of based on butene-1 fed.

COMPARATIVE EXAMPLE 1 A catalyst was prepared in the same procedure as the Example 1 except that magnesium was not contained in the catalyst, that is to say, 2 in Me was made zero. The reaction was carried out nearly the same as in that of Example 1. A higher temperature of 370380 C. of salt bath was preferred to achieve the same conversion as EX- ample 1. The catalyst composition is The result of oxidation was shown as follows:

Percent Conversion of isobutylene 94.5 Single Pass Yield of methacrolein 67.5 Single Pass Yield of methacrylic acid 3.0

The including of magnesium oxide in the catalyst composition produces a very high yield of methacrolein from isobutylene. 1,3-butadiene was simultaneously produced with a yield of 83% based on butene-1 fed.

EXAMPLES 2-8 Examples with some variations of reactions, in regard to temperature and pressure, were tried in the following Table. Catalyst and the molar ratio of feed gas were the same as Example 1.

TAB LE 1 Reaction conditions Conv., percent Single pass yield, percent Press. Contact Iso- Meth- 1,3- Temp. (atm. time butyl- Methacrylic buta- C.) 'abs.) ($00.) one Butene-l acrolein acid dlene I Example number:

N Ora-Catalyst composition ooaFe BhMgiKoqMonon.

EXAMPLES 9-17 The catalysts having the composition shown in Table Tab 2 were produced by a procedure similar to that described in Example 1. A mixed'butene' which was composed of isobutylene and butene-1 similar to that of Example 1 was used as olefins. The feed gas of olefins, air and steam Temperatures of the salt bath were also given in this EXAMPLE 29 A catalyst was prepared by the same composition and procedure as that of Example 1. The gaseous mixture of in the molar ratio of 1:2.2:6.5 were passed over the a typical spent butanes-butenes fraction, air and steam in catalyst at the contact time of 5 seconds.

TABLE 2 Single pass yield; percent Conv., percent Bath 7 Metha- 1,3

Example temp. Iso- Methacrylic' utanumber Catalysts compositions C.) buten Butane-1 crolein acid dlene 9 COsFGaBlrKomMg gMo zosa 340 96. O 96. 5 76. 5 2. 2 86. 8 10-. CosFesBirKu.o1 g2.o 01205e 325 95. 5 96. 0 74. 8 2. 5 85. 4 11 COeFegBhKu.o Mga 5M012Osa h 355 94. 8 95. 2 70. 3 3. 2 84. 4 12" CO Fe BhKmMMEI.0 0l2054 I 350 95. 0 96. 9 71. 4 2. 5 85. 2 13-.-- CoaFetBhK NlgmMonOn A 325 96.2 97. 3 76. 8 2. 3 86. 5 14 Niz. Go4.sFet.nBnKn.o1Mg1Mo O 320 95.5 96. 5 69.8 3. 4 83. 8 15.-.- Nlr.eOoe.sFes.oBirKo u Mg Mo gO g 330 96. 2 96. 4 68. 5 2. 9 84. 7 16-. CoisFesBiiKomMgiMoizosc 320 95. 5 96. 8 70. 2 2. 5 82. 1 17 C015Fe;Bi1Kc, Mg M0n0a2 320 96. 3 97. 0 68. 6 2. 8 82. 4

EXAMPLES 1 8-2 1 the molar ratio of 1:20:65 was passed over the catalyst at the contact time of about 5 seconds. The spent butanesbutenes fraction in the instant example contains 27.5% of butene-I, 48.1%0f isobutylene, 8.6% of trans-Z-butene,

0 5.6% of cis-2-butene and additional about 9.0% of butanes. The temperature of salt bath was preferred in TABLE 3 Single pass yield, percent Metha- 1,3-

Iso- Methaacrylic buta- Catalysts compositions butylene Butene-l crolein acid diene Example number:

18. COsFezBlrKnmCnMOnOsa 94. 0 95. 5 73. 3 2. 8 85. 9 19 coaFesBi Ko.o7Cro.5M01 O5c 95. 5 96. U 75. 8 2. 5 85. 4 20 CoaFmBhKamCrosMouOn 94. 3 95. 4 74. 2 3. 0 84. 9 COaFeaBhKomClanMOnOu 95. 5 96- 8 73. 5 3. O 85. O

It may also be clear from comparison with comparative Example 1 that the inclusion of chromium in the catalysts embodied herein produces a high yield of methacrolein.

EXAMPLES 22-28 the range of 330-335 C. Conversion of isobutylene and 5 Single Pass Yields obtained here were shown as follows.

Percent Conversion of isobutylene 96.0 Single Pass Yield of methacrolein 78.2

0 Single Pass Yield of methacrylic acid 2.4

The catalyst of this invention had little or no activity against butenes contained in reagent gas fed.

Single Pass Yield of 1,3-butadiene produced was about 60% based on total of normal butenes fed.

TABLE 4 Single pass yield, percent Conv.-, percent Bat Meth- Example i temp. Isobu- Methacrylic 1,3- number I Catalysts compositions C.) tylene Butane-1 acrolein acid butadiene 22-..; 'COaFesBirKu.ozMgrMOnQsc 340 95. 5 96. 2 70. 1 2. 8 84. 6 23-. oogFflzBilKfljMglMolzofl 350 95. 0 95. 5 73. 3 2. 7 85. 9 CO FEgBlrKM Mg1M012O54 350 96. 0 96. 7 69. 5 2. 5 84. 8 25 ComFezBin.sKontMgrMoizOaa 330 94.5 95. 0 68. 2 3. 1 85.6 26 C07FeaBizKo,o7Mg M01zO54 335 94. 0 95. 5 65. 4 2. 7 83. 2 27 NizCOroFBzBisKmmMgrMOmOct 320 95. 0 96. 2 70. 4 2. 5 86. 1 28-. Nl CmFeaBiiKdiu MglMo 05a 315 95. 5 95. 8 69. 4 2. 8 85. 5

7 EXAMPLE so cesium, a, b, c, d, e, f, g and h are respectively the number of atoms of Ni, Co, Fe, Bi, Me, Mo, and H and' when f is 12, a is ()to 6, b is Oto 20, c is 0.5 to 8, dis 0.1 to 7, e is less than 3 excluding zero, h is more than 0 and steam in the molar ratios of 1:2.2:6.5 was passed over no more than 05 and g 36 m the catalyst at the contact mm: of about 5 seconds and 2 A t l t 1 l 1 h 5 at 1 atmospheric pressure. This reaction is carried out at ca a as 6 mm m c alm w erem 1S 0 to a temperature of 345 C. The result was given as follows: 17 15 1 to 15, C 18 1 t0 6, d 15 1 t0 6 1S 16551112111 3 exclud- Percent ing zero, h is more than 0 and no more than 0.3, f is 12 Conversion of isobutylene 97.3 and 8 15 to Single Pass Yield of methacrylic acid 3.5 3. A catalyst as claimed in claim 1, wherein a is 0 to 5, Smgle Pass Yleld 0f methacrolem b is 2 to 12, c is 1 to 5, d is 1 to 5, e is less than 3 ex- EXAMPLES 31-59 eluding zero, h is more than 0 and no more than 0.2, f is 12 In these (elxamplesiheacl catallyst1 was prepared in the 15 and gis 40 to 70. t same proce ure as e xamp e 4 A catal st as clalm 1 'In Examples 40-59, these reactlons were carried out y ed i clafn 1 on a carnelnearly the same as that of Example 30 except reaction 5. A catalyst as claimed in claim 1, whereln the carrier temperature. The reaction is carried out at a temperature is silica. of 280 C.400 C. 20

Single pass yield Reaction percent conditions M01 ratio of Conv. oi Meth- Ex. feed gas Temp. Press. isobutylene Methaacrylic No. Catalysts composition (C4H3tOzZH3O) 0.) (atm.) percent crolein acid Sin is pass yield percent) Conv. of Meth- Meth- Example isobutylene, acroacrylic number Catalysts compositions percent lein acid 40. CoaFeeBilKomMgi.sMOizOrl 92.5 66.7 2.5 41 oosFesBilKmoiMga.oMOizOm 93. 0 65. 7 2. 3 cosFeiBiiKonMgiMoizou 94.4 63.5 2.7 8 3 i1K0.1Mg0.5M012056 92.8 66.1 2.5 Nit.5004.sFeaBilKmwMgiMonon 94.5 65.5 2.6 N11.nCm.sFeaBirKmovMgrMouOsa 94.8 66.0 2.7 COwFeaBirKo.o7Mg1M0nO5n 94.5 67.2 2.9 COuFeaBirKoaMgrMonOsz 95.0 63.5 2.8 C05FG2B11K0.07C11M0|2053 94.5 65.5 2.9 49- COQFQ5Bi1 0-0ICI'0JMO1205I 94.0 65.0 2.7 50 COsFGsBirKomCro.sMouOa: 94.2 66.1 2.5

Single pass yield,

percent Conv. oi Meth isobutylene, Methaacrylic Example number Catalysts compostions percent crolein acid 51- CogFeaBirKnmCl':.oMOrzOu 96.0 64.8 2.9 52- oosFosBisKomCImMOizOM 95.6 64.5 2.9 53. C0aF93Bi1K0.MMg1MOl206l 0 66- 2 2. 8 54. COaFGnBirKoaMgrMOn 54 95.5 65.0 2.7 55- CorFezBhKMMgiMonOn 93.7 64.4 2.7 56- COioFGgBio.5Ko.o5Mg1M0uOu 94. 0 65. 5 2. 9 57.... C07Fe3BizKo.o7Mg1M0i2OM 93.5 63.9 3.0 58--.. Ni:c010Fe2B15K0.07MgiM0i2060 95.0 63.5 3.1 59 NisCmFezBiiKo.oaMgiMOiaOn 94.5 64.0 3.0

We claim: References Cited 11.fAn ollefin oxidation catalyst represented by the gen UNITED STATES PATENTS era ormu a:

3,522,299 7/1970 Takena'ka et a1. 260604 R NiacobpecgidMeeHhMofog 3,576,764 4/ 1971 Yamaguchi et al. 252437 3,716,496 2/ 1973 Yoshino et al. 252456 X 3,642,930 2/ 1972 Grasselli et a1 260604 R in which Ni, Co, Fe, Bi, Mo and 0 respectively represent atoms of nickel, cobalt, iron, bismuth, molybdenum and oxygen, Me is at least one element selected from the group consisting of tin, chromium, zinc, manganese, titanium and tungsten, H represents at least one element selected from the group consisting of potassium, rubidium and CARL F. DEES, Primary Examiner Us. c1. X.R.- 252467; 260 -604 R 

